# Example Problems of Magnetic Circuits

From Class Wiki

# Problem 1 Kevin Starkey

Given a copper core with:

Susceptibility

Length of core L = 1 m

Gap length g = .01 m

Cross sectional area A = .1 m

Current I = 10A

N = 5 turns

Solution:
First we need to find the permeability of copper given by the equation

Which yeilds

Now using the length, cross sectional area, and permeability of the core we can solve for reluctance by:

Similarly, to get the reluctance of the gap

Now recall the equation for the magnetic field of a gap as seen in class

Yields

This is the magnetic field in the center of the gap due to the applied current

### Reviewers:

- I would change "Given: (...)[list] A copper core with..." to "Given a copper core with: [list]" to make it a little more consistent or even take all the information you have and make it into a complete sentence/paragraph.
- This looks strange to me, maybe make it or
- This sentence is kind of strange, "Now with this, the length and cross sectional area of the core we can solve for reluctance..." Maybe make it, "With the permeability, length, and cross sectional area of the copper core we can now solve for the reluctance..." Something like that might flow a little better."
- Below that, I think you need a comma after "Similarly."
- You might want to add some more words to the last two lines... Instead of saying "Now using..." say something like, "Recall that the equation for the magnetic field of the gap is..." or something to that effect.
- Lastly, you should think of some sort of conclusion... what exactly does this mean?